/**
 * @File   Hello.Cpp
 * @Author Student <3200106091@zju.edu.cn>
 * @date   Mon Sep 20 13:24:11 2021
 * 
 * @brief  A hello world example
 * 
 * 
 */
#include <iostream>
/** 
 * main function
 * 
 * @param argc number of shell paramaters
 * @param argv strings for all paramaters.
 * 
 * @return system signals.
 */
int  main(int argc,char*argv[])
{
  /// just a demo.
  std::cout <<"Hello World!"<< std::endl;
  return 0;
};
